August 01, 2021
Implants created a revolution in dentistry. The introduction of biocompatible materials that could adhere to the natural bone and at the same time mimic the lost natural tooth in both shape and function enhanced oral healthcare vastly. Placing an implant is both an extensive and a time-consuming procedure. They can be only be placed in cases where the bone density is sound after the natural tooth or teeth are lost and if the systemic condition of the patient is adequate.
Over the years, modifications have been made in implant design, materials and placements in order to re-establish the functioning of lost teeth. The basic principle that dental implants need to satisfy is called osseointegration. This is the natural mechanism that takes place in the body when the placed implant locks itself with the surrounding natural bone. It can take a couple of months for this procedure to complete, after which the final prosthesis is placed on the implant.
A conventional implant placement procedure involves removal of the damaged tooth, followed by preparation of the jawbone in the region of the lost tooth. The fixing of the implant follows and the surgical area is sutured back. Next, a waiting period ensues, that allows for osseointegration to take place. Once it is complete, the artificial tooth is placed. It is the waiting period of a couple of months or more, that dental surgeons and researchers have tried to reduce. In this quest, the 1970s welcomed the concept of immediate loading of dental implants.
The immediate loading of a dental implants is a technique where the placement of the implant is done immediately after the removal of the tooth and the final restoration is placed within 48 hours of implant placement. This technique has been more often used in the last decade with several researches claiming satisfactory osseointegration. However, a lot of factors need to be considered before opting for immediate loading. Let us have a closer look at them.
PRIMARY STABILITY
Micromotions of the implant following its immediate placement can affect the osseointegration. But it has now been accepted, that micromotions of the implant between 50-150 micrometres within the bone can result in satisfactory osseointegration.
TORQUE and BONE DENSITY
The threads of the implant screw exert a certain torque on the bone density. Following an extraction, the bone density can reduce. Once the implant is placed, the oral surgeon uses certain devices that ascertain that the bone density is adequate to resist the torque of the implant. If inadequate, the surgeon shifts to the conventional loading technique.
RADIOGRAPHIC ASSESSMENT OF BONE
Radiographs of the jawbone using CT scan be taken to study whether the bone is dense or porous. Accordingly, the implant material can be chosen for immediate loading.
ADJUNCT SURGICAL TECHNIQUE
In cases when the bone height is not sufficient, surgical procedures like grafting, sinus lift, bone condensation, etc can be done initially before an immediate loading of the implant.
SELECTION OF IMPLANT DESIGN
Now that we have a wide range of implant designs available - long, short, wide, etc., it is best judged by the clinician as to which design would suit the patient based on their missing teeth, bone density and his or her age.
PATIENT SELECTION
Immediate loading implants can be done in patients with a good oral hygiene, poor prognosis of the area of lost teeth, adequate bone density and absence of infections. These implants should not be placed in patients who are pregnant, are immunodeficient, have a systemic condition, suffering from alcohol or drug abuse and have a cyst or tumour.
AESTHETIC CONCERNS
If the patient is a good candidate for immediate implant loading, then the aesthetic concerns need to be addressed first in case the missing teeth are the front teeth. In case the missing teeth are the ones at the back, then a conventional loading implant should be considered.
OCCLUSION and WEAR PATTERN
In patients where only one tooth needs to be replaced, the dentist must evaluate the natural bite of the patient and if the force exerted by him or her is in normal limits. If the force is more, then the implant is placed such that it does not meet the teeth of the opposing arch.
IMPLANT SURFACE
Implant surfaces coated with hydroxyapatite or other bioactive materials help in faster osseointegration and should thus be considered for immediate loading.
The most commonly encountered complications after immediate loading of implants includes fracture of the prosthesis, loosening of the implant, improper fit of the final restoration and inadequate healing of surrounding tissues. All these factors can be countered by making tbe necessary adjustments and none of them are fatal for the patient.
Immediate loading of dental implants is a time-saving implant placement technique that can address the patient's oral health needs faster. However, assessment of the bone is of paramount importance before opting for this technique.